Apparatus for drying thread or the like



Oct. 20, 1942.

L. .1, JORDAN ETAL APPARKTUS FOR DRYING THREAD OR THE LIKE Filed Sept. 7, 1937 5 Sheets-Sheet 1 v Isnventor; VERN JJORDAN AND CLARENCE C. WALTERS w mmflflomeg Oct. 20, 1942- L. J. JOREIJAN ETAL 2,299,239

APPARATUS FOR DRYING THREAD OR THE LIKE Filed Sept. '7, 1937 3 Sheets-Sheet 3 3maentors LAVERN J. JORDANAND CLARENCE GWALTERS Patented Oct. 20, 1942 UNITED, STATE PATENT OFFICE APPARATUS FOR DRYING THREAD OR v THE LIKE Lavern J. Jordan, Fairview Village, and Clarence C. Walters, Cleveland, Ohio, assignorl to Industrial Rayon Corporation, Cleveland, Ohio, a

corporation of Delaware Application September '7, 1937, Serial N0. 162,701

5 Claims.

' This invention relates to apparatus for drying thread-like materials such as filaments, cords,

bands, tapes, tubes, etc., hereinafter referred to consequently, it is possible to collect the thread immediately in package form.

An important feature of the invention is the employment of apparatus of such shape that substantially all of the energy radiated from the heating means thereof is caused to be directed upon the thread passing therethrough. Inasmuch as practically all of the energy emitted by the heating means thus reaches the thread, the efliciency of the apparatus as a whole is of a high order. A lower consumption.of energy by the heating means, a shorter length of drying tube or both is thereby made possible.

Another significant feature of the invention is the proportioning of the heating means so as to radiate different amounts of heat upon the thread at different points in its path of travel through the apparatus, preferably relating the amount of heat radiation to the condition of the thread. It has been found that an advantageous drying procedure is to subject the thread to more heat during the initial stages than during the latter stages of the drying operation. This de-, parture from prior-practices in the drying procedure of the present invention results in important advantages, as will hereinafter appear.

While the invention is hereinafter disclosed in connection with the manufacture of artificial silk thread by the viscose process, it may be employed to advantage in other processes, such as the cuprammonium, cellulose nitrate, and cellulose acetate processes.

Two embodiments of the invention are disclosed in the accompanying drawings, in which Figure l is a front elevation of the'lower portion of a continuous thread-processing machine in which is embodied a first form of thread-drying apparatus. Figure2 is a sectional elevation on the line 2-4 of Figure 1. larged section with parts in elevation on line 33 of Figure 1. Figure 4 is a section on the line- 4-4 of Figure 3. Figure 5 is a plan of the device of Figure 3. Figure 6 is a front elevation on an enlarged scale of the upper portion of the device of Figure 3. Figure 7 is a perspective of a second embodiment of the invention, parts thereof being shown as separated. Figure 8 is a perspective of the apparatus of Figure 7, the parts being in closed position. Figure 9 is a section on the line 9-9 of Figure 8. Figure 10 is a section on an enlarged scale on the line ilk-III of Figure 9.

Referring first to Figures 1 and 2, the threaddrying apparatus I0 is shown asdisposed below a drip reel l2 to which thread H is supplied from a. wash reel l3 disposed thereabove. Reels l2 and II are the lowermost two of a series of reels which are arranged one above the other to form a descending series. The reels may be and preferably are offset from each other in such manner that the thread-receiving portion of each reel is immediately below the thread-discharge portion of the reel thereabove, an arrangement which expedites the transfer andrunning of the thread between reels. For a similar reason, it is desirable that the thread-drying apparatus Ill be disposed below the thread-discharge portion of the drip reel II.

In a complete thread-processing machine, several descending series of reels each with its associated thread-drying apparatus are positioned side by side as shown in Figure l. arrangement, it is possible to utilize a common supply duct disposed longitudinally of the machine for delivering processing liquid to the reels of the several series upon which the same processing step is performed. For example, a water supply pipe [4 may be common to the several distributors l5 which shower washing fluid upon the wash reels l3. 1

The several reels of each descending series may be geared to and rotated by an inclined drive shaft l6. Shaft it, as well as reels l2 and i3, is supported by an inclined beam i'l mounted upon rail l8 extending longitudinally of the machine.

' The several drive shafts I6, of which there is one Figure3isanenfor each descending series of reels, are driven by a common shaft 20 disposed longitudinally of the machine.

Reels l2 and I3 are representative of any device which, upon rotation thereof, serves to advance in a plurality of generally helical turns thread stored on the device. The reel here shown comprises two rotatable reel members having their axes disposed in offset and inclined relation and having the axis of one reel member disposed within the periphery of the other reel member. Each reel member comprises a plurality of longitudinally extending bar members disposed in interdigitating relation with those of the other member. Such reels are With this shown, described and claimed in Knebusch fatcat 2,210,914.

Upon passing over drip reel l2, much of the excess liquid upon the thread II is removed. However, upon leaving reel l2, the thread ll may still have a liquid content at least as high as if not greater than 300% and this considerable amount of moisture must be removed in order to prepare the thread for collection. As here shown, the thread ll, after leaving the threaddrying apparatus I0, is collected by a cap-twister l9. Where a cap-twister is employed, it is desirable that the thread be dry or nearly dry.

Thread-drying apparatus It includes a tubular member through the interior of which the thread H is passed. Within the tubular member is a metal sheet 22 of such shape that any transverse cross-section through such tubular member is of generally elliptical shape. The edges 23 of metal sheet 22 are not brought together, but are flared outward to form an entrance 24 to the interior of the tubular member. It is desirable that the internal surface of metal sheet 22 be polished in order to provide high heat-reflecting qualities.

The upper and lower ends of the tubular member are closed by plates 25 and 26 in which are formed slots 21 and 28 extending inward from the periphery of the plate toward the center thereof. When in proper position upon the ends of the metal sheet 22, these slots 21 and 28 register with the entrance 24 to the interior of the tubular member. To secure plates 25 and 25 on the metal sheet 22, any desired means such as a weld 29 may be used. i

Extending longitudinally of the metal sheet 22 and opposite entrance 24 is a channel 3|, the open side of which faces toward the metal sheet 22. Upon the exterior of metal sheet 22 and extending between the flared ends 23 thereof and the channel 3| is a thick layer of heat-insulating material 32. The presence of this heat-insulating material and the channel 3| prevents escape of heat from the exterior of the tubular member.

Within the interior of the tubular member and extending between the end plates 25 and 26 is an electrical resistance wire 33 of helical formation. As appears from Figure 4, the wire passes through all cross-sections of the tubular member at the focal point opposite entrance 24. It is desirable that the turns of the resistance wire 33 at the upper portion thereof be closer together than the turns at the lower portion of the wire in order that more heat may be radiated from the upper portion than from the lower portion. The upper and lower ends of the wires 33 may be respectively connected to insulating blocks 34 and 35 which are secured to end plates 25 and 28. From the insulating blocks 34 and 35 con necting wires 35 and 31 may extend through the channel 3| and out through an opening 38 in the rear wall thereof for connection to line wires 15 and 11.

In assembling the tubular member in the upper end of resistance wire 33 and one end of wire 35 are secured to the insulator block 34 carried by the upper end plate 25, which plate is thereupon secured in position upon the upper end of metal sheet 22; The lower end of resistance wire 33 is then connected on insulator block 35 to an end of wire 31. The lower end plate 25 may then be brought against and secured to the lower end of metal sheet 22. Channel 3| may then be applied of waires 36 and 31 be brought out through open- 18 8.

To fasten the tubular member to the frame of the thread-processing machine it may be secured to a U-shaped bracket 40 having arms 4| and 42. Arm 42 of the bracket is secured by bolts 44 to a channel member 45 secured within rail l8. Extending between the arms4| and 42 near their free ends is a spacer member 46 which serves to maintain these arms in fixed relation. The tubular member is secured to arm 4| by screws 43 passing through the rear wall of metal sheet 22 and through the rear wall of channel 3|. In this manner the channel 3| is clamped tightly against the exterior of metal sheet 22.

Immediately above. the tubular member is disposed a pair of squeeze rollers 41 and 48. The shafts 49 and 50 for these squeeze rollers are rotatably supported in bosses carried by arm 4| of bracket 40. Gears 49 and 50, cause a positive rotation of the squeeze rollers 41 and 48 at the same peripheral speed. To drive squeeze rollers 41 and 48 from the inclined shaft iii an intermediate drive shaft 54 is provided. Shaft 54 is carried in bearings provided by bosses on the arms 41 and 42 of the bracket 40. At one end of shaft 54- is a bevel gear which meshes with gear 55 upon the inclined shaft "5. Near its other end shaft 54 carries a spur gear 51 which meshes with gear 52 upon shaft50.

Below the tubular member 22 is a pair of squeeze rollers 59 and 35 carried upon shafts 6i and 62 which are rotatable in bosses carried by arm 4| of the bracket 48. Shafts 6i and 52 are connected together by gears 53 and 64 so that the surfaces of squeeze rollers 59 and Eli will be positively rotated at the same speed. Shaft 62 is driven from shaft 55 through a vertical shaft 55 which is rotatable in bearing bosses carried by the connecting member of bracket 40 and the spacer member 45. Vertical shaft 85 is connected to shaft 58 through bevel gears 86 and is connected to shaft 82 through bevel gears 51.

Squeeze roller 48 is so disposed that its periphery is vertically in line with the focus nearest the iiared edge 23 of the elliptical metal sheet 22. Squeeze rollers 59 and 60 are so disposed that the line of contact between them is to the exterior of metal sheet 22 and the free ends 7 vertically below the same focus. Immediately above squeeze rollers 41 and 48 is a guide eye 68 and immediately below squeeze rollers 53 and 50 is a guide eye 18. Guide eye 68 is so located that it will cause thread to pass around the portion of squeeze rollers 41 and 48which will result in movement of the thread through all cross-sections of metal sheet 22 at that focal point which is nearest the entrance 24. ,Guide eye 18 prevents thread movements thereof arising from cap-twister i9 from reaching rollers 59 and 60.

Due to the passage of the thread through one of the focal points of all transverse crosssections through metal sheet 22 and due to the fact that the electric wire 33 is located at the other focal points of these same cross-sections, practically all of the heat radiated from the resistance wire will be directed upon the thread. This is due to the fact that the metal sheet is shaped in the form of an ellipse in crosssection and the fact that the focal points of this ellipse are conjugate fuel. In Figure 4 several lines of radiation have been drawn out to show the manner in which heat from wire 33 is reflected upon thread H. In this manner the 5| and 52, secured toshafts 39 will be most efiiciently used in drying the thread.

Due to removal of moisture from the thread in drying it will tend to shrink during its passage from squeeze rollers 41 and 49 to squeeze rollers 59 and 89. By varying the ratio between gears 55 and 81 squeeze rollers 59 and 89 may be rotated at a different peripheral speed with respect to the peripheral speed oi squeeze rollers ll and 48. It is thus possible to rotate rollers -59 and 99 at such lower speed with respect to the speed of rollers ll and 48 that the thread will shrink to the full extent to which would normally shrink it unrestrained in its passage through the tubular member. If desired, this shrinkage may be limited by rotating squeeze rollers 59 and 99 at a greater rate of speed than the speed of rotation which they would have if such unrestrained shrinkage were to occur. By properly relating the peripheral speed of rollers 91 and 48 to rollers 59 and 829, any desired residual shrinkage may be imparted to the thread. If squeeze rollers 59 and 99 have the same peripheral speed as rollers ll and 13, no shrinkage of the thread will be permitted. I

Squeeze rollers 4'! and 548 not only serve-to deliver thread at the proper position in the tubular member but additionally serve to squeeze from the thread the excess moisture thereon. The fluid so removed collects upon the lower roller 49 and to remove this fluid a wiper blade H may forcibly bear upon roller 98. This wiper blade is carried by a rod 12 held in opposite ends of a trough '19 which is carried by arm ill of the U bracket. Water which is collected in the trough l3 may be conducted by pipe M to a common discharge conduit 15 extending longitudinally of the machine.

In operation, the thread is drawn from drip reel i2 and passed at once to the cap-twister l9. Thereafter the thread is looped through guide eyes 69 and 70 and allowed to pass over the exterior surface of the tubular member. It is then possible to pass the thread between the upper pair of squeeze rollers 4'1 and 48 and between the lower pair or squeeze rollers 59 and 59 and to allow the thread to enter through opening 24 into the interior of the tubular member.

Any desired control means may be provided to regulate the current delivered to wire 33. The resulting radiant heat which is emitted may thereby be controlled. By regulating the amount of elec ic l e y supplied to the resistance wire 33 and by properly proportioning the length of the tubular member to the electrical energy consumed and to the amount of moisture to be removed from the thread, the thread may be dried to any desired extent, so that upon issuing from the tubular member it may be collectedupon cap-twister 19.

The closer spacing of the turns of resistance wire 33 at the upper portion thereof than at the lower portion proportions the heat radiated from the electrical wire along the length of the tubular member to the requirements for drying the thread at difierent stages in its passage through the tubular member. Upon. entering the tubular member, the thread may contain a certain amount of free surfacemoisture which is not removed by passage of the thread between squeeze rollers 41 and 48. This free surface moisture may be readily removed from the by the application of considerable heat to the thread and this is achieved by the close spacing of the turns of the electrical wire.

After the surface moisture has been removed from the thread the internal moisture must be removed. This internal moisture, since it must he removed by diffusion, requires a considerably longer time for its removal. By spacing the turns of the electrical wire at a greater distance apart at the lower end of the tubular member, only that amount of heat will be radiated upon the thread which'is necessary to cause removal of the internal moisture of the thread. if a greater amount of heat were radiated upon the thread at the lower portion of the tubular member, as, for example, would result if all the turn spacings were as close together as the turns at upper portion of the resistance wire, the thread would be subjected to greater heat than could be utilized.

The tubular member 89 disclosed in Figures 7 to 9, inclusive, may be substituted for the tubular member of Figures 1 and 2, being positioned between squeeze rollers ill and 8 and squeeze rollers 59 and 69. The metal sheet 9! of this tubular member is so shaped that the portions thereof on each side of the minor .axis of the cross-sections of the tubular member will be of parabolic shape in cross-section and these two parabolic sections are symmetrical; two endsof the metal sheet iii are flared outward to form an entrance 82 to the interior of the tubular member 39. Upon the ends of metal sheet 8! are positioned closure plates 93 and 9 having slots 85 and 89 therein registering with entrance 82 to admit thread to the interior of the tubular member. If desired, heat insulation may be applied to the exterior of the metal sheet 9 l I Extending longitudinally of each parabolic section 01': metal sheet 9i inisuch position that they lie at the focal point of cross-sections thread.

. essential'since the wire may be straight.

through each parabolic section are resistance wires 87 and 85. In order to increase the heat energy radiated from this resistance wire it is desirable that it be coiled in helical form although it will be understood that this is not The ends of each of the Wires 9! and 58 are attached to-terminal posts 89 and 99 carried by the upper and lower end plates 89 and 35.

Within the interior or the tubular member is secured a ba 92 extending longitudinally thereof and disposed at the minor axis of crosssections of the tubular member. Projecting from bar 92 at spaced intervals are lingers 93] In the outer ends of fingers 99 are formed grooves 95 to receive the thread passing through the tubular member and guide it in its passage. Pivotally connected to the lower end of bar member 92 is a second bar member 95 having projecting perpendicularly therefrom at spaced intervals, fingers 96. Grooves 91 in the ends of bars 96 receive thread passing through the tubular member. Fingers 96 are so disposed along bar 95 that they will lie midway between fingers 93 when the bar 95 is brought toward bar 92 as in Figure 8. To limit inward movement of bar 95 it is provided with stop 1ugs-99 which will strike against the exterior of the tubular member. Bar 95 will be retained in closed position relative to bar 92 as shown in Figure 8 by spring pressure exerted upon bar 95 by the flared outer ends of metal sheet 8 l.

ltd passing through the bar 92, through the wall of metal sheet and through the wall of channel as may be secured into an arm of a U bracket corresponding to it disclosed in Figures, 1 and 2. The screws M0 in this manner serve to retain all of the parts of the apparatus in assembled position. Lead wires Hill and me which extend through the channel 99 may be connected to the binding posts 89 and 88 at opposite ends of the tubular member,

In placing the apparatus in operation, the. arm 95 is withdrawn from the arm @2 to assume the position shown in Figure 7. The thread then may be introduced into the'interior of the tubular member through entrance 82 and guide eyes corresponding to es and it in Figure 2 will causethe' thread to lie within the grooves 9 3 in fingers 93. Thereafter the bar may be swung inwardly'toward the tubular member and be clamped in position as shown in Figure 8 by the flared ends of the metal sheet. When in this position, the fingers at will force the thread lying between fingers 33 toward the bar 92 so that the thread will pass through the tubular'member in the sinuous form shown in Figure 8.

By bending the thread back and forth in this manner throughout the length of the tubular member and due to the disposition of the thread in the plane of the minor axis of cross-sections through the tubular member 36, a considerable length of thread will be exposed aaeaaeo ever features of patentable novelty reside in the invention.

What is claimed is:

1. Apparatus for drying wet thread comprising a generally tubular member the inner surface of which consists in transverse cross section of two parabolas facing each other, each parabolic portion of said surface having a focal line extending longitudinally of said tubular member; means lying in each of said focal lines for emitting radiant heat; and mean for guiding thread through said to the heat radiated from resistance wires 8? and 83. ln'this manner a very efiicient use of the heat energy emitted by the resistance wires will be had since the thread will be curved back and forth across the lines along which the heat is radiated after reflection from the curved parabolic surfaces of metal sheet 8!. In Figure 9 several radiation lines are represented to show their passage across the thread.

In the embodiments of the invention here described it will be observed that the heating element is disposed at-the focal line of a curved surface which in cross-section has a focal point. In each such embodiment the heating element throughout its length lies in the locus of all of the focal points of all transverse cross-sections through the tubular member with which the heating element is associated. Furthermore, in the embodiments of the invention disclosed, the thread is so disposed that it receives the major portion of the heat which is radiated from the heating element and which is reflected from the curved inner surface of the tubular member.

It will be understood that variation may be made in the apparatus here disclosed without departing from the spirit of the invention. For example, it is not necessary thatthe squeeze rollers either above the tubular member or below the tubular member be employed. Furthermore, it is to be understood that a feature disclosed in connection with one embodiment of the invention may be incorporated in a like position in the other embodiment of the invention; for example, the heating element 33 having differential spacings of its turns may be utilized in the apparatus disclosed in Figures 7 to 10, if desired, in order to obtain the benefits arising from the spacing.

It is intended that the patent shall cover, by suitable expression in the appended claims, whattubular member in convoluted formation in the plane separating said parabolic portions.

2. Apparatus for drying wet thread comprising a generally tubular member part of the inner surface of whlch'consists in transverse cross section 'of a parabola; means for emitting radiant heat lying inthe focal line of the parabolic inner surface of said generally tubular member. said heat-emittingmeans being so constructed and arranged that itdelivers more heat toward one end thereof than toward the other; and means for guiding the thread through said generally tubular member in a path spaced from the heatemitting means but exposed to heat reflected from the parabolic inner surface of the generally tubular member.

3. Apparatus for drying wet thread comprising a generally tubular member the inner surface of which consists in transverse cross section of an ellipse; means for emitting radiant heat lying in one of the focal lines of the elliptical inner surface of said generally tubular member, said heatemitting means being so constructed and arranged that it delivers more heat toward one end thereof than toward the other; and means for guiding the thread through said generally tubular member in a path coinciding with the other focal line of the elliptical inner surface of the generally tubular member.

4. Apparatus for drying wet thread comprising a generally tubular member which embodies a longitudinally extending reflecting surface having two associated focal lines; radiant heat-emitting means extending longitudinally of said generally tubular member at one of the focal lines of said reflecting surface, said heat-emitting means being so constructed and arranged that it deliver more heat toward one end thereof than toward the other; and means for guiding the thread in a path extending longitudinally of the generally tubular member, said path coinciding with the other of said focal lines.

5. Apparatus for drying wet thread comprising a generally tubular member which embodies a longitudinally extending reflecting surface having an associated focal line; radiant heat-emitting means extending longitudinally of said generally tubular member at the focal line of said reflecting surface, said heat-emitting means being so constructed and arranged that it delivers more heat toward one end thereof than toward the other; and means for guiding the thread in a path extending longitudinally of the generally tubular member, said path being spaced from the heat-emitting means but exposed to heat reflected from the reflecting surface.

LAVERN -J. JORDAN. CLARENCE C. WALTERS. 

